At the end of the day, these pirogues are moored in the sand exploitation harbor of Kalaban Koro, a former fishing village a few miles upriver from Bamako on the right bank of the Niger River. Extraction of sand from the riverbed is an attempt to meet the Malian capital’s growing demand for sand and gravel for construction. The fast growth of this city of 1.8 million inhabitants – there were 130.000 inhabitants in 1960 - is fed by a rural exodus in one of the poorest countries on earth, where the population lives on less than $1 a day. Yet this extremely hard work attracts young Malians from all over the country. Working for a salary and sometimes owning their own pirogue, these «sand fishermen» hold their breath and dive to the river bottom where they fill a bucket with sand, which another worker pulls up by rope, pouring its contents into the pirogue. Although this activity is entirely ‘handmade’, they manage to extract millions of cubic meters of sand a year, up and down river from Bamako. As a consequence the riverbed is getting lowered and the existing dams or the planned ones above the city limit the transport of sediments.